YAEDA VALLEY, Tanzania -- One of the last remaining tribes of hunter-gatherers on the planet is on the verge of vanishing into the modern world.

The transition has been long underway, but members of the dwindling Hadzabe tribe, who now number fewer than 1,500, say it is being unduly hastened by a United Arab Emirates royal family, which plans to use the tribal hunting land as a personal safari playground.

The deal between the Tanzanian government and Tanzania UAE Safaris Ltd. leases nearly 2,500 square miles of this sprawling, yellow-green valley near the storied Serengeti Plain to members of the royal family, who chose it after a helicopter tour.

A Tanzanian official said that a nearby hunting area the family shared with relatives had become "too crowded" and that a member of the Abu Dhabi royal family "indicated that it was inconvenient" and requested his own parcel.

The official, Philip Marmo, called the Hadzabe "backwards" and said they would benefit from the school, roads and other projects the UAE company has offered as compensation.

But dozens of Hadzabe interviewed deep in the scruffy hills surrounding this valley said that while they are ready to modernize, slowly, they were not consulted on the deal, which is a direct threat to their way of life because it involves hunting.

While they have through 50,000 years survived the coming of agriculture, metal, guns, diseases, missionaries, poachers, anthropologists, students, gawking journalists, corrugated steel houses and encroaching pastoral tribes who often impersonate them for tourist money, the resilient Hadzabe, who still make fire with sticks, fear that the safari deal will be their undoing.

"If they are going to come here, we definitely will all perish," said Kaunda, a Hadzabe man who prefers khakis but still hunts with hand-hewn poison arrows. "Our history will die, and the Hadzabe will be swept off the face of the world. We are very much afraid."

Their fear is based on a similar agreement the government struck years ago with another company that resulted in dozens of Hadzabe men being arrested for hunting on tribal land. Three of the men died of illness in the bewildering environment of prison, cut off from the open world, their daily hunting and their diet of herbs, roots and honey. Three others died soon after being released.

"We're not used to that kind of life in jail," said Gudo, an elderly Hadzabe whose best friend, Sumuni, was among those who perished. "Sumuni was my age. Our fathers were friends. We played together, learned how to hunt together," he said, looking away. "I don't want to talk anymore."

A recent meeting in the Yaeda Valley on the issue ended with several Hadzabe men shouting at Tanzanian government officials for ignoring them. One of the men was later charged with disruptive behavior and jailed for several days. Two others who have spoken against the deal said they have been threatened with arrest and are now on the run, moving from hut to hut to elude police.